Auxiliary wheel assembly for expandable luggage item

ABSTRACT

An auxiliary wheel assembly for supporting expandable luggage items is provided. The auxiliary wheels are installed beneath the front cover of the expandable luggage item. When the luggage item is expanded and the front cover is moved outward, the auxiliary wheels are synchronously moved along with the front cover. The luggage item therefore could always maintain an upstanding state regardless of how much content is stored inside the luggage item.

BACKGROUND OF THE INVENTION

(a) Technical Field of the Invention

The present invention generally relates to luggage items, and more specifically to an auxiliary wheel assembly for expandable luggage items.

(b) Description of the Prior Art

These days an item of luggage is commonly found with two or four wheels attached to the bottom of the luggage item. With the help of a telescopic handle or a pull strap, the luggage item could be easily pulled for a safe and convenient transportation of its content. Recently there is a design that combines the wheeled luggage item with an expandable main compartment so that the space inside the luggage item could be flexibly enlarged if required. Originally the design has the wheels of the luggage item fixed at the positions based on the state when the luggage item is retracted. However, when the luggage item has its compartment expanded and inevitably has its center of gravity shifted, the luggage item becomes difficult to handle and difficult to keep upstanding when it is still. To overcome these shortcomings, as shown in FIGS. 5-7, there is a design utilizing an additional, retractable wheel assembly 21 at the center of the luggage item's bottom 20.

The wheel assembly 21 is equipped with one or two wheels 22 that could be extended for a fixed distance to support the luggage item when its compartment 23 is expanded. If the compartment 23 is expanded only marginally, the wheels 22 would be extended too far out, causing difficult operation and collision hazard for the luggage item. On the other hand, if the luggage compartment 23 is expanded to its maximum capability, the extension of the wheels 22 might not be long enough, causing again difficulties in operation. Therefore, there is a need for a better auxiliary wheel assembly design that can support an expandable luggage item regardless how much its compartment has expanded.

SUMMARY OF THE INVENTION

The primary purpose of the present invention is to overcome the aforementioned difficulties in the conventional auxiliary wheel assembly.

The present invention directly installs the auxiliary wheels beneath the front cover of the expandable luggage item. When the luggage item is expanded and the front cover is moved outward, the auxiliary wheels are synchronously moved along with the front cover. The luggage item therefore could always maintain an upstanding state regardless of how much content is stored inside the luggage item.

The foregoing object and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts.

Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an expandable luggage item with an auxiliary wheel assembly according to a first embodiment of the present invention.

FIG. 2 is a perspective bottom view showing an expandable luggage item with an auxiliary wheel assembly according to a first embodiment of the present invention.

FIG. 3 is a side view showing an expandable luggage item with an auxiliary wheel assembly according to a first embodiment of the present invention.

FIG. 4 is a perspective bottom view showing an expandable luggage item with an auxiliary wheel assembly according to a second embodiment of the present invention.

FIG. 5 is a perspective view showing an expandable luggage item with a conventional auxiliary wheel assembly.

FIG. 6 is a perspective bottom view showing an expandable luggage item with a conventional auxiliary wheel assembly.

FIG. 7 is a side view showing an expandable luggage item with a conventional auxiliary wheel assembly.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following descriptions are of exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims.

In the following, detailed description along with the accompanied drawings is given to better explain preferred embodiments of the present invention.

Please refer to FIGS. 1 to 4. As illustrated, an item of an expandable luggage item includes a main frame 10, a front cover 11, and a flexible joining member 13 that goes around the perimeters of the main frame 10 and binds the front cover 11 to the main frame 10. A zipper 12 is installed along the edges of the main frame 10 and the front cover 11 such that, by undoing and doing up the zipper 12, the joining member 13 could be stretched or shrunk and the compartment (not numbered) formed by the main frame 10 and the front cover 11 could be expanded or retracted. As shown in FIGS. 1 and 2, there is a wheel frame 14 at the bottom edge of the front cover 11, which has two wheels 15 fixedly installed to the two ends of the wheel frame 14. When the luggage item is expanded or retracted, the wheel frame 14 and the attached wheels 15 moves along with the front cover 11. The wheel frame 14 and the wheels 15 therefore give proper support to the enlarged section of the luggage item when it is expanded. Besides having the wheel frame 14 as a one-piece molded structure, in another embodiment as illustrated in FIG. 3, two separate wheels 16 could be independently installed at the bottom corners of the front cover 11. The bottom edge of the front cover 11 is protected by a rigid connecting board 17.

For the first embodiment using a one-piece wheel frame 14, the wheel frame 14 not only reinforce the rigidity of the front cover 11's bottom edge, but also facilitate the adjustment of the wheels 15 to be aligned with the other wheels (not numbered) of the luggage item on the same horizontal level. Most importantly, as the joining member 13 is stretched and the front cover 11 is moved outward, the locations of the wheels 15 are synchronously and directly shifted to the bottom of the outmost part of the luggage item. The luggage item is therefore always able to maintain a steady upstanding state regardless how much content is stored inside the luggage item. Compared to the extendable auxiliary wheel design of prior arts, the present invention does not require separate manipulation or extension of the auxiliary wheels, which is more convenient and easy to use.

It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.

While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention. 

1. An auxiliary wheel assembly for an expandable luggage item comprising a wheel frame installed at a bottom edge of a movable front cover of said expandable luggage item and at least a wheel fixedly attached to said wheel frame, said auxiliary wheel assembly characterized in that, when said expandable luggage item is expanded and said movable front cover is moved outward, said wheel frame and said wheels are synchronously moved along with said front cover to as to support the enlarged space of said expandable luggage item.
 2. The auxiliary wheel assembly for an expandable luggage item according to claim 1, wherein said wheel frame has a molded one-piece structure.
 3. An auxiliary wheel assembly for an expandable luggage item comprising a plurality of wheels installed at bottom corners of a movable front cover of said expandable luggage item and a connecting board for protecting a bottom edge of said front cover, said auxiliary wheel assembly characterized in that, when said expandable luggage item is expanded and said movable front cover is moved outward, said wheels and said connecting board are synchronously moved along with said front cover to as to support the enlarged space of said expandable luggage item. 